[SDKS-7516] Create FlagSetSanitizer to validate flag sets

client/src/main/java/io/split/client/SplitClientConfig.java

@@ -16,6 +16,8 @@
 import java.util.Properties;
 import java.util.concurrent.ThreadFactory;
 
+import static io.split.client.utils.FlagSetSanitizer.sanitizeFlagSet;
+
 /**
  * Configurations for the SplitClient.
  *
@@ -195,7 +197,6 @@ private SplitClientConfig(String endpoint,
         _threadFactory = threadFactory;
         _flagSetsFilter = flagSetsFilter;
 
-
         Properties props = new Properties();
         try {
             props.load(this.getClass().getClassLoader().getResourceAsStream("splitversion.properties"));
@@ -921,8 +922,7 @@ public Builder customStorageWrapper(CustomStorageWrapper customStorageWrapper) {
          * @return this builder
          */
         public Builder flagSetsFilter(List<String> flagSetsFilter) {
-            _flagSetsFilter = flagSetsFilter;
-            //TODO Apply validations
+            _flagSetsFilter = sanitizeFlagSet(flagSetsFilter);
             return this;
         }
 

client/src/main/java/io/split/client/utils/FlagSetSanitizer.java

@@ -0,0 +1,46 @@
+package io.split.client.utils;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+public final class FlagSetSanitizer {
+
+    private static final String FLAG_SET_REGEX = "^[a-z0-9][_a-z0-9]{0,49}$";
+    private static final Logger _log = LoggerFactory.getLogger(FlagSetSanitizer.class);
+
+    private FlagSetSanitizer() {
+        throw new IllegalStateException("Utility class");
+    }
+
+    public static List<String> sanitizeFlagSet(List<String> flagSets) {
+        if (flagSets == null || flagSets.isEmpty()) {
+            _log.error("FlagSets must be a non-empty list.");
+            return new ArrayList<>();
+        }
+        HashSet<String> sanitizedFlagSets = new HashSet<>();
+        for (String flagSet: flagSets) {
+            if(flagSet != flagSet.toLowerCase()) {
+                _log.warn(String.format("Flag Set name %s should be all lowercase - converting string to lowercase", flagSet));
+                flagSet = flagSet.toLowerCase();
+            }
+            if (flagSet.trim() != flagSet) {
+                _log.warn(String.format("Flag Set name %s has extra whitespace, trimming", flagSet));
+                flagSet = flagSet.trim();
+            }
+            if (!Pattern.matches(FLAG_SET_REGEX, flagSet)) {
+                _log.warn(String.format("you passed %s, Flag Set must adhere to the regular expressions %s. This means an Flag Set must be " +
+                        "start with a letter, be in lowercase, alphanumeric and have a max length of 50 characters. %s was discarded.",
+                        flagSet, FLAG_SET_REGEX, flagSet));
+                continue;
+            }
+            sanitizedFlagSets.add(flagSet);
+        }
+        return sanitizedFlagSets.stream().sorted().collect(Collectors.toList());
+    }
+}

client/src/test/java/io/split/client/SplitClientConfigTest.java

@@ -195,9 +195,9 @@ public void checkDefaultRateForFeatureAndSegment() {
 
     @Test
     public void checkSetFlagSetsFilter() {
-        List<String> sets = Stream.of("test1", "test2").collect(Collectors.toList());
+        List<String> sets = Stream.of("test1", "test2", "TEST3", "test-4").collect(Collectors.toList());
         SplitClientConfig config = SplitClientConfig.builder().flagSetsFilter(sets).build();
         Assert.assertNotNull(config.getSetsFilter());
-        Assert.assertEquals(2, config.getSetsFilter().size());
+        Assert.assertEquals(3, config.getSetsFilter().size());
     }
 }

client/src/test/java/io/split/client/utils/FlagSetSanitizerTest.java

@@ -0,0 +1,57 @@
+package io.split.client.utils;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FlagSetSanitizerTest {
+
+    @Test
+    public void testEmptyFlagSets() {
+        List<String> flagSets = new ArrayList<>();
+        List<String> cleanFlagSets = FlagSetSanitizer.sanitizeFlagSet(flagSets);
+        Assert.assertTrue(cleanFlagSets.isEmpty());
+    }
+
+    @Test
+    public void testUpperFlagSets() {
+        List<String> flagSets = new ArrayList<>();
+        flagSets.add("Test1");
+        flagSets.add("TEST2");
+        List<String> cleanFlagSets = FlagSetSanitizer.sanitizeFlagSet(flagSets);
+        Assert.assertEquals("test1", cleanFlagSets.get(0));
+        Assert.assertEquals("test2", cleanFlagSets.get(1));
+    }
+
+    @Test
+    public void testTrimFlagSets() {
+        List<String> flagSets = new ArrayList<>();
+        flagSets.add(" test1");
+        flagSets.add(" test2 ");
+        List<String> cleanFlagSets = FlagSetSanitizer.sanitizeFlagSet(flagSets);
+        Assert.assertEquals("test1", cleanFlagSets.get(0));
+        Assert.assertEquals("test2", cleanFlagSets.get(1));
+    }
+
+    @Test
+    public void testRegexFlagSets() {
+        List<String> flagSets = new ArrayList<>();
+        flagSets.add(" test1");
+        flagSets.add(" test-2 ");
+        List<String> cleanFlagSets = FlagSetSanitizer.sanitizeFlagSet(flagSets);
+        Assert.assertEquals(1, cleanFlagSets.size());
+        Assert.assertEquals("test1", cleanFlagSets.get(0));
+    }
+
+    @Test
+    public void testDuplicateFlagSets() {
+        List<String> flagSets = new ArrayList<>();
+        flagSets.add(" test1");
+        flagSets.add(" test1 ");
+        List<String> cleanFlagSets = FlagSetSanitizer.sanitizeFlagSet(flagSets);
+        Assert.assertEquals(1, cleanFlagSets.size());
+        Assert.assertEquals("test1", cleanFlagSets.get(0));
+    }
+}